The soil nematode, Caenorhabditis elegans (C. elegans), is a promising model organism to assess the effects of potential developmental and neurological toxicants on multi-cellular organisms. However, to determine the possibility of using C. elegans as a practical and efficient model in toxicology studies, medium throughput technologies must be created to monitor phenotypic characteristics including growth, size, reproduction, feeding, and movement. Methods in current practice are not conducive to medium-throughput studies because they are often manual and laborious to perform. There is a noticeable lack of computerized automated quantitative C. elegans analysis tools that perform well in the presence of differing experimental conditions. We propose to develop a commercial product that will be composed of a computerized microscope system that allows investigators to perform advanced automated, quantitative analyses of the locomotion and other complex behaviors of freely moving C. elegans nematodes. We believe that introduction of a robust commercial software solution will significantly contribute to further replacement and reduction of conventional toxicology tests by alternative in vivo toxicology assays using C. elegans. Public Health Relevance: The proposed project will enable research using the model organism, Caenorhabditis elegans (C. elegans), to occur at a faster pace than is currently feasible by allowing complex and laborious tasks currently performed manually to be done automatically. This will allow researchers to increase the throughput of studies involving quantitative behavioral analysis. The overall effect of this project will significantly improve the productivity and effectiveness of research in such diverse fields as toxicology, environmental monitoring, ecology and neuroscience research. [unreadable] [unreadable] [unreadable]